Xfi aux input settings no change with any values

redsled579

Member
Joined
Apr 2, 2009
Bought xfi plug and play setup from cal a few months back, then i added caspers fuel and oil pressure logging kit. Ive been behind all summer assembling new drivetrain and installing in car, so i havent done much with stock file. just trying to get these 2 sensors setup correctly for when fire up comes.

So far: jumper is set in caspers conversion box
Aux 1 relabled to fuel psi and aux 2 to oil psi
Both read with no pressure 13-14 psi on laptop dash and e dash
Hooked up air pressure regulator to each sensor and both readings rise with added pressure very close to what i add in air pressure.
I did the 2 pressure point/raw voltage point equation to get gain and offset and my math comes out correct, have checked several times.
I made the necessary changes from the from factory 25 and -25 and saved changes. But seems like no matter what numbers I put in the readings on dash never change. Ive tried even off the wall numbers and still stays the same. Am I missing something?
 
Bought xfi plug and play setup from cal a few months back, then i added caspers fuel and oil pressure logging kit. Ive been behind all summer assembling new drivetrain and installing in car, so i havent done much with stock file. just trying to get these 2 sensors setup correctly for when fire up comes.

So far: jumper is set in caspers conversion box
Aux 1 relabled to fuel psi and aux 2 to oil psi
Both read with no pressure 13-14 psi on laptop dash and e dash
Hooked up air pressure regulator to each sensor and both readings rise with added pressure very close to what i add in air pressure.
I did the 2 pressure point/raw voltage point equation to get gain and offset and my math comes out correct, have checked several times.
I made the necessary changes from the from factory 25 and -25 and saved changes. But seems like no matter what numbers I put in the readings on dash never change. Ive tried even off the wall numbers and still stays the same. Am I missing something?
Couple of things,
1 - What version are you running ? 2.01, 2.05 ?
2 - On Version 2.05 there are 2 fuel and oil pressure parameters that can be viewed in the Dashboard. One is calibrated in the AUX analog setup menu, the other is calibrated in the system configuration/sensor calibration menus.
AG.
 
Couple of things,
1 - What version are you running ? 2.01, 2.05 ?
2 - On Version 2.05 there are 2 fuel and oil pressure parameters that can be viewed in the Dashboard. One is calibrated in the AUX analog setup menu, the other is calibrated in the system configuration/sensor calibration menus.
AG.
I am running 2.05 and just looked at that table and its correct also at 1 volt = 0 psi and 5v = 100psi.

Its almost like its not saving the changes. Ive tried changing values in the tune in other places just to see if it is ideed flashing the pcm and it is. I would think if i had something connected wrong they just wouldnt work at all but they do. Just off by +13 psi

Original sensor gain was 25 and offset was -25, but they say needs adjusted sometimes. So i did the 2 pressure values for equation. I got 2.41v at 20psi and 4.98v at 100psi. Plug those in the equation in the help section i come up with gain of 31.128401 and offset of -55.019402

Ive tried both these and any other number, just doesnt change the values at all
 
I am running 2.05 and just looked at that table and its correct also at 1 volt = 0 psi and 5v = 100psi.

Its almost like its not saving the changes. Ive tried changing values in the tune in other places just to see if it is ideed flashing the pcm and it is. I would think if i had something connected wrong they just wouldnt work at all but they do. Just off by +13 psi

Original sensor gain was 25 and offset was -25, but they say needs adjusted sometimes. So i did the 2 pressure values for equation. I got 2.41v at 20psi and 4.98v at 100psi. Plug those in the equation in the help section i come up with gain of 31.128401 and offset of -55.019402

Ive tried both these and any other number, just doesnt change the values at all
What type of sensors ? Are you sure they are wired correctly ? The Fast SSI sensors need 12v supply. I would check that first.
AG.
 
your sensor doesnt make sense ..you should have seen 2.4v at 50 not 20 !
 
What type of sensors ? Are you sure they are wired correctly ? The Fast SSI sensors need 12v supply. I would check that first.
AG.
It is the caspers kit for xfi with pnp harness to the egr wiring. Instructions shows that both sensors are 5v sensors and the tags on both sensors show 5v and 100psi ratings.

your sensor doesnt make sense ..you should have seen 2.4v at 50 not 20 !
I agree now that i think of that it makes sense. The instructions shows it to be linear sensor with 1v=0psi and 5v =100psi so in theory 3v should net me 50psi. I just checked now sensor open to air is showing 1.55v. I have a couple pics to double check. Car has a new caspers engine wiring harness and all new grounds so can pretty much eliminate that.
 

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OOPS you should see 50 AT 3V
still a big error in that sensor that should be reading 1v at 0psi

and that ss1 sensor is labeled 5v indicating its output range is 1-5v .. input is still 12v (actually 8-30 works) and thats how the casper plug and play harness off the egr plug should have it
if sensor had 4.5 on label it would have an output of .5-4.5 which is common on the cheap sensor from ebay
 
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OOPS you should see 50 AT 3V
still a big error in that sensor that should be reading 1v at 0psi

and that ss1 sensor is labeled 5v indicating its output range is 1-5v .. input is still 12v (actually 8-30 works) and thats how the casper plug and play harness off the egr plug should have it
if sensor had 4.5 on label it would have an output of .5-4.5 which is common on the cheap sensor from ebay
Ok, im going to try to bench test sensors later. It just stumps me that any change in the sensor setup doesnt change the value of the output at all
 
If you are still hung up, don't hesitate to call me. I'm tuning at Indy this week, but should be able to talk
 
If you are still hung up, don't hesitate to call me. I'm tuning at Indy this week, but should be able to talk
Thanks Cal. I still need to call you for the inital setup check over for my xfi system. Got it a few months back, just wanted to get all loose ends tied up that I can before calling you. It is a fresh motor, turbo, went xfi, tr6 ignition and new engine harness, so i am triple checking everything before 1st fire up . Hopefully ill be in contact with you by weeks end.
 
Are you sure you are making these changes with the computer on-line and communicating with the XFI ?
AG.
 
Yes ive tried connecting then making changes, ive tried offline then loading, no difference. My thoughts right now are why is it reading 1.55v open to air on the sensor (makes me think wiring, but it is a caspers kit with harness and sensors specific for an xfi), but still changing settings for the sensors should change the psi shown even if its not correct.
 
Yes ive tried connecting then making changes, ive tried offline then loading, no difference. My thoughts right now are why is it reading 1.55v open to air on the sensor (makes me think wiring, but it is a caspers kit with harness and sensors specific for an xfi), but still changing settings for the sensors should change the psi shown even if its not correct.
Regardless if you change the gain or offset there should be a change in reading. I would also check and make sure you are actually changing channels 1 and 2 and then make sure the auxiliary inputs of XFI test out with the appropriate caspers harness pins.
AG.
 
Regardless if you change the gain or offset there should be a change in reading. I would also check and make sure you are actually changing channels 1 and 2 and then make sure the auxiliary inputs of XFI test out with the appropriate caspers harness pins.
AG.
Thats what i was thinking first, but they actually work fone they are just 13psi high. here is 3 pics with air regulator connected to fuel press sensor. 1st one is at rest reading 13 psi, then roughly 20 psi, 50psi, and 80psi. All 13psi high. It read 96 on the 80 psi, but cheap regulator im sure not super accurate. All steps in psi exactly the same with oil pressure sensor
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Just to be clear, you're changing the values in the FP & OP sensor calibration? They are located at:
View/System Configuration/sensor calibration/FP Sensor. You are inputting the voltage at 0 & 100psi
You should NOT be messing with the gain and offset values in the Aux channels
 
Thats what i was thinking first, but they actually work fone they are just 13psi high. here is 3 pics with air regulator connected to fuel press sensor. 1st one is at rest reading 13 psi, then roughly 20 psi, 50psi, and 80psi. All 13psi high. It read 96 on the 80 psi, but cheap regulator im sure not super accurate. All steps in psi exactly the same with oil pressure sensorView attachment 261538 View attachment 261539 View attachment 261540 View attachment 261543

I did dot realize you are using the eDash. Have you tried viewing this through the FAST main Dash ? Again, 2.05 has separate parameters for fuel and oil pressure and not sure how the eDash is configured to look at that. I would verify the sensor calibration first in the sensor calibration menu as Cal suggested.
AG.
 
As Cal said, make sure you are calibrating the FP and OP sensor from the sensor calibration menu. Another thing to consider is that the sensors in the Casper's kit are not the same sensors as FAST sells. I believe they both run on 12 volts and with the Casper's adapter that plugs into the EGR connector, that's where it will get the voltage. However, the Casper's sensors are absolute pressure sensors while the FAST sensors are relative (gauge) pressure sensors. The calibration and behavior will be different.
 
I was changing gain and offset in aux sensor setup with no change in reading so i set them back to original readings. I did try under system configurations setting low voltage to 1.55 (what my sensors are reading raw at 0psi). That does 0 them out on laptop dash and e dash (they have both always coincided). But now the readings are off because sensors range is different. Theoretically I should just be able to change gain and offset to correct it and lose any number over 87psi where it is now reading full sensor voltage of 4.99(my 13psi that I showed at 0), but like before any change makes no difference
 
As Cal said, make sure you are calibrating the FP and OP sensor from the sensor calibration menu. Another thing to consider is that the sensors in the Casper's kit are not the same sensors as FAST sells. I believe they both run on 12 volts and with the Casper's adapter that plugs into the EGR connector, that's where it will get the voltage. However, the Casper's sensors are absolute pressure sensors while the FAST sensors are relative (gauge) pressure sensors. The calibration and behavior will be different.
I had that thought this morning 13psi roughly atmospheric that they could be absolute sensors, but I figure caspers had to sell a bunch of these kits and I wouldnt be the 1st one with a problem. I guess contacting him would be next step here
 
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